Some battery-driven electronic devices such as mobile telephones, digital cameras, PDA (Personal Digital Assistants) and the like have a function for near field radio communication using infrared rays.
The mobile electronic devices have a serious problem that a power consumption should be suppressed since they are driven by batteries. Thus, in the infrared communication function, too, supply of an electric power to an infrared communication unit is stopped until en instruction to execute infrared communication is given by the user, and the electric power is thereby saved.
In such a conventional near field radio communication apparatus, however, there is a problem that the user needs to execute a plurality of key operations to turn on the near field radio communication function via a user interface, which is useless for the user and inconvenient for, particularly, aged persons who are unfamiliar with operations of the electronic device.
Recently, an electronic device is equipped with a solar power generation panel, and a battery thereof is thereby charged.